The invention generally relates to operator control of autonomous heavy machinery and specifically to methods for human operators to use autonomous vehicles in agriculture, construction, and open-pit mining.
A significant amount of work has been done to improve the efficiency of heavy machinery in areas such as agriculture, construction, and open-pit mining. In particular, some efforts strive to improve effectiveness of the equipment by providing very accurate position information to the driver or even automatically steering the vehicle.
Most prior art does not explain what the operator should do when an unplanned obstacle or boundary is encountered. Some approaches strive for complete autonomy, with no human operator, in which case a variety of sensors are directed to try to handle atypical situations. Others propose a combination of autonomous, semi-autonomous, and manual modes of operation, without describing ways for the operator to interact with the system to achieve specific results.
Parkinson et al., U.S. Pat. No. 6,052,647, xe2x80x9cMethod and System for Automatic Control of Vehicles Based on Carrier Phase Differential GPS,xe2x80x9d describes an auto control system for a land vehicle based on carrier phase differential GPS for position and heading sensing.
Gudat et al., U.S. Pat. No. 5,646,843, xe2x80x9cApparatus and Method for Surface Based Vehicle Control System,xe2x80x9d and Gudat et al., U.S. Pat. No. 5,615,116, xe2x80x9cApparatus and Method for Autonomous Vehicle Navigation Using Path Data,xe2x80x9d discuss auto control of a land vehicle with distinct operating modes and path following. Simple methods for switching between autonomous and manual modes are described but are different from the invention described herein. Obstacle avoidance operates purely autonomously. Neither disclosure describes a way for the operator to make corrections to the auto guidance plan without switching to manual mode.
The following patents relate to automatic path planning and trajectory following but do not discuss a user interface or a method for the user to adjust the trajectories:
Brandt et al., U.S. Pat. No. 6,085,130, xe2x80x9cMethod and Apparatus for Selecting a Transition Scheme for Use in Transitioning a Mobile Machine from a First Path to a Second Pathxe2x80x9d relates to a transition from one path to another path, presumably under complete autonomy.
Zimmerman et al., U.S. Pat. No. 6,041,870, xe2x80x9cMethod and Apparatus for Steering a Dozing Machine,xe2x80x9d describes actuation of a dozer blade to laterally adjust the centerline of the vehicle.
Keller et al., U.S. Pat. No. No. 5,987,383, xe2x80x9cForm Line Following Guidance System,xe2x80x9d covers a method for automatically generating paths.
Rao, U.S. Pat. No. 5,684,696, xe2x80x9cSystem and Method for Enabling an Autonomous Vehicle to Track a Desired Path,xe2x80x9d describes generation of a desired trajectory based on current location and desired trajectory.
Sarangapani et al., U.S. Pat. No. 6,064,926, xe2x80x9cMethod and Apparatus for Determining an Alternate Path in Response to Detection of an Obstacle,xe2x80x9d Sarangapani, U.S. Pat. No. 6,173,215, xe2x80x9cMethod for Determining a Desired Response to Detection of an Obstacle,xe2x80x9d and Sarangapani, U.S. Pat. No. 5,752,207, xe2x80x9cMethod and Apparatus for Determining a Path for a Machine between a Predetermined Route and a Final Position,xe2x80x9d all describe automatic path planning and obstacle avoidance.
Motz et al., U.S. Pat. No. 6,236,924, xe2x80x9cSystem and Method for Planning the Operations of an Agricultural Machine in a Field,xe2x80x9d describes a path planning method.
The following patents pertain to vehicle control:
Motz et al., U.S. Pat. No. 6,205,381, xe2x80x9cSystem and Method for Planning the Operations of an Agricultural Machine in a Field,xe2x80x9d relates to coordination of multiple vehicles under automatic control.
Staub et al., U.S. Pat. No. 6,236,916, xe2x80x9cAutoguidance System and Method for an Agricultural Machine,xe2x80x9d relates to general auto control of farm tractors.
Gharsalli et al., U.S. Pat. No. 6,062,317, xe2x80x9cMethod and Apparatus for Controlling the Direction of Travel of an Earthworking Machine,xe2x80x9d relates to control systems for construction scraper.
Sin et al., U.S. Pat. No. 5,657,226, xe2x80x9cSystem and Method for Causing an Autonomous Vehicle to Track a Path,xe2x80x9d relates to general auto control of farm tractor.
Herein is taught a method for adjusting a desired trajectory of an automatically guided vehicle guidance system to match a physical constraint such as an obstacle or boundary. The method works around obstacles and boundaries as they occur, consistent with the original trajectory. The method is independent of the type of vehicle. The method may be used regardless of whether the vehicle is under automatic guidance, and the method has a low computational cost.